中文摘要：

针对无线传感器网络节点能量难以补充，如何延长网络使用寿命的问题，将网络工作过程描述为不定阶段动态规划问题，结合总能量守恒关系推导出网络寿命上下界，提出能量优先的聚类轮换策略并证明了其最优性．在此基础上，设计了实用性好的最小切换聚类轮换算法（SSLL），利用PowerTOSSIM仿真验证了SSLL取得接近最优的网络寿命．

英文摘要：

Wireless sensor networks （WSN） are promising in many military and civil applications. Due to the difficulty of energy recharging, prolonging the lifetime of WSN systems is one of the key challenges. The working process of WSN is formulated as a variable-stage dynamic programming problem. The upper bound and lower bound of system lifetime are derived based on the energy conservation law. An energy-first cluster rotation statgey is proposed and proved to be the optimal, based on which, a practical smallest switching longest lifetime cluster rotation algorithm （SSLL） is proposed. Simulation results with PowerTOSSIM verify that the SSLL algorithm achieves almost optimal system lifetime.